A method is presented for achieving high entrapment efficiencies of a hydrophilic drug simulant, sulforhodamine B (SRB), in nanometer-scale liposomes using a continuous-flow microfluidic system. Liposome size and size dispersion are determined using tandem Asymmetric Flow Field Flow Fractionation (AF4) and Multi-Angle Laser Light Scattering (MALLS). The average number of encapsulated SRB molecules in a single liposome is measured with Fluorescence Correlation Spectroscopy (FCS) and Fluorescence Cumulant Analyis (FCA). Our results show that this system allows for controlled loading of SRB into the liposomes with high entrapment efficiencies (EE) measured as a ratio of SRB concentration inside the liposome to SRB starting concentration in the hydration buffer.
Proceedings Title: Proceedings of the 12 International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS 2008)
Conference Dates: October 12-16, 2008
Conference Location: San Diego, CA
Pub Type: Conferences
liposomes, encapsulation, microfluidics, viscosity anisotropy